Watched the most recent WNO, and have watched others, and the inconsistency of the scoring for "sub only" as its termed just means no points are awarded and there is a vague sense of submissions versus positional grappling being awarded. The event with the Atos' Ruotolo brothers and Renzo's Nicky Ryan and Ethan Crelinsten comes to mind. I don't doubt that it went 1-1 across the two matches, but if Nicky lost due to positional dominance by one brother then Ethan should've won his match by asserting that same dominance and passing against the other brother. Watching the Maysa vs Grace match also came to mind. Granted, the match was close in the sense that neither really passed decisively, and the real danger of any foot locks or otherwise is debatable but, the lack of scoring points leads to at best subjective scoring, and at worst, the historically validated preferential treatment by judges/refs that has plagued the sport as a result of the myriad of those involved in scoring/reffing who have some affiliation by degrees of separation to someone's coach or teammate or even the competitor.
Bias against leg locks and attacks or lack of information is apparent in the valuation of fake foot lock attacks to accrue attacks in F2W. Guys will spend 8 minutes (in the Gi in particular) cranking on a foot lock from 50/50 when there's minimal risk in said position. The IBJJF and the Oscar worthy toe hold in the waning seconds as the guy looks like he's in a bathhouse orgy scene springs to mind. I saw this not as an indictment against "sub only" but rather that longer match duration and not scoring points leaves an even more prone to interpretation decision-making criteria that is likely not consistent across 3 judges. I thought Thor won the match against Rocha. Rocha passed one time, briefly, and otherwise was largely stymied in passing due to various leg lock attempts and entries. If a top player finds himself withdrawing from contact, butt to mat, and fleeing away from his opponent, the attempt to disengage should function at least comparable to an opponent turtling to avoid a guard pass. I appreciate the removal of points to encourage more submission attempts, but much like wrestling and Judo have implemented, actually using stalling calls creates urgency on the part of competitors, or forces a decision to play it safe at the risk of losing or being DQ'd.
I appreciate the value to having different rule sets across grappling styles, and even within the same sport. ADCC forces most serious entrants to work on their wrestling and backtakes. Sub only forces more diligence with leg entanglements and overtime positions. Points awarding formats force positional awareness and the importance of scoring first.
No time limit sub only feels the least compelling. Sure, competitors can take more chances, but by the 20-30 min mark, it is often a war of attrition with less and less action occurring. BJJ Bishop did a great breakdown of the finish rate and win rate relative to scoring and match length (back when the Abu Dhabi Pro instituted short match lengths in an effort to encourage more action and less stalling). What it showed was that changing the match length from 10 minutes (IBJJF) to 6 minutes (Abu Dhabi Pro) even at the black belt level had little effect on the % of matches that ended in submission. What did change was that the percentage of impact the first score had on predicting the winner of the match rose. IE: first score in a shorter match is a much likelier indicator of winning than in a longer match.
Submission Underground has a truly short 5 minute regulation with no points, then overtime. From a spectator standpoint, it keeps matches visually more attune to a casual fan base (ala why he uses more MMA fighters with name recognition et cetera), but add to that the cage and you end up with some matches where guys cage wrestle and stand on the feet for 5 minutes, then it's Overtime. If a competitor chooses to disengage, they can easily run down the better part of 5 minutes, even in a cage, particular when you add in clinch/wrestling, and/or against a seated opponent.
I've competed in a lot of 5 minute points matches at Grappling Industries in the past 3 years. I've also done a lot of EBI format events. I also did an EBI Overtime only format event this past year. Overall, the more I do sub only events, the less engaging I find them. If at it's core, JiuJitsu is a combat sport, the idea that an opponent can be mounted for 7 minutes, have their back taken, escape bunch of leg entanglements seems self-defeating. Given that few submissions statistically come in the 8-10 minute mark, if you're doing a 16 man bracket, the draw/pools determining who faces who and in what order has a more signifcant impact on the event as it wears on.
I did the SoGI -155 Pro bracket this Fall, and by the finals, I had something like 34 minutes of mat time, with two matches going to OT. My first match went 10 minutes regulation, then 6 OT rounds, and I won on ride time. My 2nd match I finished via heel hook in -1 min. My third match went 10 minutes regulation then I won by RNC in the 4th OT round. The finals I lost in regulation roughly 4-5 mins in. I say this not to place blame, but rather as examining the format and looking for meaning in determining regulation duration versus OT rounds et cetera.
I'm all for the purist part of JiuJitsu which at its core is a blend of positional dominance and/or resultant submission. I (probably because I fought MMA and played Judo for 10 years) appreciate the utilization of stalling calls to force engagement. A lot of what is passed off as being technical and other silly terms commentators use (because of the hero worship in JiuJitsu) is actually just guys doing as little as possible or avoiding danger.
There's a fine line between using position to score points and ride out the remainder of time or relentlessly spamming leg attacks with no potential of finishing, in the sense that they are both artificial and disingenuous. As events compete for viewership or simply offer content for fans, it's interesting to see the resulting skills and game plans change.